How to remove a broken screw?

[Jalbao]

I have a screw with a broken head that goes through the floor board .

Does anyone have any ideas how I can remove the screw ?

I've tried to unscrew it with vice grips, but it keeps slipping.

 

[Strait Cruisin]

Grind it off flat. The hole stays plugged that way.

Does it need to be replaced? Again grind it off flat and give it a wack with a pin punch.

 

[My71FJ40]

With a bit of luck and a lot of cursing. OK, that is a placebo but one way if you have to would be cut/grind it off flush then you should be able to see diameter of the bolt compared to the tub and drill through the center of the bolt with a small pilot bit like 1/8 then go up to 80% of the diameter of the bolt and drill it out. Once that is done you should be able to knock it out with a punch because now you would have greatly weakened it and should only have mostly the treads left IF you were careful and drilled straight and directly in the center. Oh, is it into the frame also? What is on the other side...be careful. Good luck!